S-substituted phenyl N-alkyl-thiolcarbamates which are described as active against the specific fungus, Pythium ultimum, are disclosed in U.S. Pat. No. 4,056,549. Certain other thiolcarbamates have been described as effective against various plant pests, and as being herbicides, insecticides, miticides, etc. U.S. Pat. No. 3,265,563 describes S-phenyl N-alkylthiolcarbamates, S-chlorophenyl N-alkylthiolcarbamates, S-ethoxyphenyl N-allylthiolcarbamates, S-ethoxyphenyl-N-alkylthiolcarbamates, S-p-tolyl N-alkylthiolcarbamates, and S-2,4-dimethylphenyl N-alkylthiolcarbamates as herbicides and fungicides.